Figure 2. Conductance–voltage relationships (G–Vs) for DI–DIV S6 cysteine mutants.

Normalized G–Vs for (a) DI, (b) DII mutants, (c) DIII and (d) DIV mutants were generated by measuring the peak tail currents elicited from inside-out patches containing mutant channels over a range of potentials. All patches were held at −120 mV and subjected to varying ranges of depolarizations depending on the particular mutant. Conductance values were normalized by dividing the peak tail current value at a given voltage by the maximum tail current value obtained and fit to a Boltzmann function to determine V_1/2 and Z values (Table 1).